Well perforator indexing apparatus



Oct. 27,1964 c P LANMON 11 3,154,147

WELL PERFORATOR INDEXING APPARATUS Filed Feb, 24, 1959 C P Lev/7m 0/7 I INVENTUR.

f U "MM! #Jww ATTOR/Vfy United States Patent 3 154 147 WELL PERFURATOEQ IIEDEXING APPARATUS C P Lanmon TI, Friendswood, Tex, assignor to Sclllurnherger Well Surveying Corporation, Houston, Tex., a

corporation of Texas Filed Feb. 24, 1959, Ser. No. 794,877 13 Claims. (Cl. 166-551) This invention relates to indexing systems and, more particularly, to indexing systems for borehole apparatus to translate relative longitudinal motion between two members into relative rotational motion between the members in a predetermined manner.

It is an object of the present invention to provide new and improved indexing systems for borehole apparatus to translate relative longitudinal motion between two members into relative rotational motion.

Another object of the present invention is to provide new and improved indexing systems for an apparatus for conjunctive use with well perforating apparatus.

Still another object of the present invention is to provide new and improved indexing systems for small diameter well tools adapted to pass through tubing wherein the indexing means permits continuous indexing through a number of angular positions by surface manipulation of a supporting cable.

A still further object of the present invention is to provide new and improved indexing systems for a small diametered well tool which permits an increased number of angular positions to be obtained.

These and other objects of the present invention are accomplished by a cylindrical member slidably receiving a tubular member, the members being relatively movable with one of the members having indexing slots therein and the other member having a follower for the slots. The indexing slots include a plurality of longitudinally extending slots disposed about the periphery of the cylindrical member and interconnected by inclined or transverse slots. The bottom wall portion of the slots is varied in depth and includes shoulders formed in the slots to provide an irreversible progression from slot to slot.

The novel features of the present invention are set forth with particularity in the appended claims. The present invention, both as to its organization and manner of operation together with further objects and advantages thereof, may best be understood by way of illustration and example of certain embodiments when taken in conjunction with the accompanying drawings in which:

FIG. 1 illustrates the present invention embodied in an exemplary apparatus which is disposed in one of a pair of tubing strings in a borehole;

FIG. 2 is a cross-sectional view taken along line 2-2 of FIG. 1;

FIG. 3 is a developed view of the periphery of the indexing mandrel and slot system embodying the present invention;

FIG. 4 is a cross-sectional view taken along line 4-4 of FIG. 3;

FIG. 5 is a cross-sectional view taken along line 5-5 of FIG. 3;

FIG. 6 is a cross-sectional view taken along line 6-6 of FIG. 1 illustrating a portion of the indexing system of the present invention; and

FIG. 7 is a cross-sectional view of a portion of the apparatus taken along line 7-7 of FIG. 6.

The apparatus of FIG. 1 with which the present invention may be employed is illustrated and completely described in the copending application of M. Lebourg field February 24, 1959, S. N. 795,099 and assigned to the assignee of the present invention. Therefore, such apparatus will be briefly described herein only so far as 3,154,147 Patented Get. 27., 1964 necessary for an understanding of its relation to the present invention.

As shown in FIG. 1, borehole 10 traverses earth formations 11, 12 and receives coextending tubing strings 13 and 14. A tool 15 to perforate the tubing 13 and formations 12 without perforation of the adjacent tubing 14 is suspended in tubing 13 by a cable 16 and spooled from a winch 17 at the surface of the earth in a customary manner. Tool 15 includes a casing collar locator 18, an indexing mandrel 19 and a perforator 20 interconnected together to form a unitary assembly, the indexing mandrel 19 being slidably received within the bore 21 of centralizer 22 (see FIG. 6). Centralizer 22 is provided with plurality of friction springs 23 which, in a well-known manner, frictionally engage the inner wall of the tubing thereby retarding relative movement between the centralizer and the tubing.

The lower portion of indexing mandrel 19 is provided with means to form a beam of radiation 24 which may consist of gamma rays emitted from a shielded radiation source 25 through an opening on one side. A slot system 26 located above the source 25 on mandrel 19 cooperates with a follower 27 (see FIG. 6) on the centralizer 22 to promote rotation of the mandrel (and the beam) relative to the centralizer (frictionally secured to tubing 13). A gamma ray detector 28 suspended in tubing 14 by a cable 29 connected to a spooling winch 30 at the surface of the earth detects the intensity of the emitted gamma rays while a recorder means 31 electrically connected to the detector 28 records the intensity of gamma rays received by the detector at various rotated positions of the beam of radiation 24 thereby to permit orientation of the beam of radiation 24.

Perforator 20 is provided with shaped charges 32, 32', or the like, having firing axes 33, 34 (represented by the arrows in FIG. 2) phased at to one another and disposed at right angles to the beam of radiation 24. Other charges in the perforator would similarly have firing axes which would fall in a longitudinal plane extending through the perforator and through firing axes 33, 34. Hence as indexing mandrel 19 is cycled through a number of rotative indexing positions, the intensity of the radiation is plotted relative to each indexing position to provide an indication of the direction of the beam of radiation thereby permitting orientation of the firing axes 33, 34 relative to tubing 14. When axes 33, 34 are oriented as in FIG. 2, a source of power 35 at the surface of the earth may be connected through conventional circuitry to perforator 20 to detonate charges 32 32' to perforate tubing 13, the cement and formation 12 without perforating tubing 14.

Referring now to FIG. 3, a simplified indexing slot system 26 in which the present invention is embodied includes identically arranged slots 36 which extend longitudinally of the mandrel 19 and have upper and lower portions 37, 38, respectively. Each of the slots 36 is rectangular in cross section having a uniform width defined between parallel side wall surfaces 39, 40 and a perpendicularly disposed bottom wall surface 41. Identically arranged slots 42 are inclined relative to longitudinal slots 36 and respectively interconnect a lower portion 38 of one longitudinal slot to the upper portion 37 of an adjacent longitudinal slot. Each inclined slot 42 is rectangular in cross section having a uniform width defined between parallel sidewall surfaces 43 and 44 which have a spacing therebetween similar to that of sidewall surfaces 39, 40 of longitudinal slots 36, and a perpendicularly bottom wall surface 45. While only four longitudinal slots 36 and four inclined slots 42 are shown by way of example, it will be understood that the number as well as the relative positionment of the slots may be varied Within the scope of this invention. Hence,

it will be appreciated that a continuous slot system 26 is formed by the longitudinal and inclined slots 36, 42, the entire system assuming an H shape with the cross slots inclined relative to the longitudinal slots.

For simplicity of description, only one longitudinal and one inclined slot need be described, it being understood that the other slots of the system are similarly arranged.

Referring now to FIGS. 3 and 4, the bottom wall 41 of a slot 36 includes an upper section 46 at a depth d from the outer periphery of the mandrel 19, an intermediate elevated section 47 at a depth d/2 from the outer wall of the mandrel, an outwardly inclined section 48 connecting the upper section 46 to elevated section 47 and a lower section 49 at a depth d from the outer periphery of the mandrel, the lower section 49 and elevated section 48 forming a downwardly facing shoulder '50. Shoulder 50 is inclined relative to the sidewall surfaces 39, 40 of slot 36 so as to constitute an extension of the sidewall surface 43 of an inclined slot 42.

Referring now to FIGS. 3 and 5, the bottom wall surface 45 of an inclined slot 42 includes a lower section 51 at a depth d from the outer periphery of the mandrel 19 which is continuous with wall section 49 of slot 36, an upper elevated section 52 at a depth d/ 2 from the outer periphery of the mandrel and an outwardly inclined section 53 connecting lower section 51 to upper section 52. Upper section 52 opens into sidewall 39a of the adjacent slot 36a at a location above inclined section 48a of adjacent slot 36a, the section 46a of slot 36a and elevated section 52 forming a shoulder 54 which is a portion of the sidewall 39a.

Referring now to FIG. 6 for details of the follower for the indexing slot system 26, the tubular centralizer 22 has at its upper end an annular groove 55 of rectangular cross section which receives a G-shaped member 56. Member 56 has a complementary rectangular cross section to groove 55 and is formed from resilient spring material to clamp in the groove. At one end of member 56, the follower 27 is formed from an end portion which extends radially inward into register with the slot system 26 through an opening 57 (see FIG. 7) in the bottom wall of the groove 55. Follower 27 has an extremity 2711 which extends into contact with the bottom wall surface of the slot system 26 and is canted or inclined slightly relative to the longitudinal axis of the mandrel (see FIG. 7) for reasons which will become more apparent in the description of the operation. Indexing mandrel 19 is also provided with a central bore 58 to pass electrical conductors (not shown) through the mandrel.

In an exemplary operation of the above-described indexing system, the tool 15 is lowered to a desired level in the tubing 13 where the follower 27 is held in a relatively fixed position by the centralizer 22. In an initial con dition, the indexing follower 27 may be in the upper end portion 37 of a slot 36 near the position A (FIG. 3). By raising the mandrel 19 relative to follower 27 (by winch 17 or by hand), the follower 27 moves relative to bottom wall section 41 of slot 36 until extremity 27a of follower 27 engages inclined bottom wall section 48 whereupon the follower 27 is cammed outwardly against the resilient force of spring member 56. Thereafter, the extremity 27a of follower 27 rides along elevated wall section 47 and, upon passing over shoulder 50, the resilient force of spring member 56 urges the follower 27 into contact with the lower wall section 49 of slot 36 and the follower 27 will go towards position B at the lower end 38 of slot 36. The indexing mandrel 19 is then lowered and the extremity 27a of follower 27 Will engage shoulder Continued downward movement of mandrel 19 produces rotation of the mandrel since follower 27 will transfer into inclined slot 42, the transfer being facilitated by the like inclination of the shoulder 50 and follower 27. Extremity 27a of follower 27 will subsequently engage inclined section 53 of inclined slot 42 and hence follower 27 will be cammed outwardly against the resilient force of spring member 56. Thereafter, the extremity 27a of follower 27 rides along the elevated wall section 52 and, upon passing over shoulder 54, the resilient force of spring member 56 urges the follower 27 into contact with the upper section 46a of slot 36a. Extremity 27:: therefore is in contact with wall section 46a and continuing downward movement of mandrel 19 causes follower 27 to go towards position C in the upper end 37 of slot 36. Thus, the mandrel has been rotated through an angle as determined by the angular spacing between the longitudinal slots 36. The cycle of operation as above described may then be repeated any number of times in a similar fashion, each cycle producing a rotation of the indexing mandrel 19.

As a practical example of the compactness of abovedescribed indexing system for use with a tool, in a 2 LD. tubing, a mandrel having a diameter of 1 may be utilized having at least 12 longitudinal slots spaced at from one another about the periphery of the mandrel, each slot having a wides of A a depth d of and a depth d/2 of 5 The length of the slots may, of course, be selected for any particular application, and a slot length of 30 has been found to be adequate to compensate for longitudinal movement of the mandrel due to the detonation shock on the perforator 21). Spring member 56 may be, for example, made from clock spring material thick and A," wide to snap in groove 55 which is in width and in depth.

While particular embodiments of the present invention have been shown and described, it is apparent that changes and modifications may be made without departing from this invention in its broader aspects, and therefore the aim in the appended claims is to cover all such changes and modifications as fall within the true spirit and scope of this invention.

What is claimed is:

1. Apparatus for use in a well bore comprising: a tubular member including having means to frictionally engage the walls of a well bore; a mandrel slidably received by said member and adapted to be supported by a cable; said mandrel having indexing slot means arranged about its periphery for indexing rotatively said mandrel relative to said member in one rotative direction only; a follower on said member adapted to cooperate with said slot means to rotate said mandrel relative to said member; and a well tool having a selected direction of operation connected to said mandrel for rotation therewith.

2. Apparatus for use in a well bore including a cylindrical member arranged for connection and movement with a cable, a tubular member slidably received on said cylindrical member, wall engaging means coupled to said tubular member and operative for retarding longitudinal movement of said tubular member relative to a well bore, said cylindrical member having indexing slot means about its periphery, said tubular member having a groove in its outer wall and an opening between said groove and the inner wall of said tubular member, a spring member received by said groove having an end portion arranged to extend through said opening into register with said slot means thereby to form a follower for said slot means.

3. Apparatus for use in a well bore including a cylindrical member arranged for connection and movement with a cable, a tubular member slidably received on said cylindrical member, wall engaging means coupled to said tubular member for retarding longitudinal movement of said tubular member in a well bore, said cylindrical member having indexing slot means about its periphery said tubular member having a annular groove in its outer wall substantially rectangular in cross section and an opening between said annular groove and the inner wall of said tubular member, a unitary spring member having a complementary rectangular cross section received by said annular groove having an end portion extending radially and inwardly through said opening into register with said slot means thereby to form a follower for said slot means.

4. Apparatus for use in a well bore comprising: a tubular member, wall engaging member coupled to said tubular for effectively retarding longitudinal movement of said tubular member relative to the side wall of a bore; a cylindrical member slidably received by said tubular member and adapted to be supported by a cable; said cylindrical member having slot means arranged about its periphery to index said cylindrical member relative to said tubular member; said slot means including longitudinal slots and transverse connecting slots which provide a continuous slot system about said cylindrical member; a follower on said tubular member received by said slot means; transfer means in said slot means cooperable with said follower for irreversibly transferring said follower from slot to slot upon reciprocation of said cylindrical member relative to said tubular member thereby rotatively indexing said cylindrical member; and perforator apparatus connected to said cylindrical member for rotation therewith.

5. Apparatus for use in a well bore including a cylindrical member arranged for connection and movement with a cable, a tubular member slidably received on said cylindrical member, wall engaging means coupled to said tubular member and operative for retarding longitudinal movement of said tubular member relative to a well bore, said cylindrical member having slot means about its periphery providing a continuous slot system and including slots with portions of different relative depths, said tubular member having a recess in its outer wall and an opening between said recess and the inner Wall of said tubular member, a follower member mounted in said recess and having an end portion arranged to extend to said opening into register with said slot means, said follower member being constructed of spring material and normally resiliently biased into register with said slot means.

6. Apparatus for perforating in a well bore penetrating subsurface formations, said well bore having at least two, spaced-apart pipe strings arranged therein comprising a gun perforator having a selected direction of fire arranged in one of said pipe strings; gun perforator positioning means adapted to position said gun perforator to direct the direction of fire thereof in any selected direction in a 360 arc including cage means provided with means for engaging the interior wall of said one pipe string to restrain movement of said cage means, and means connected to said gun perforator, one of which means being provided with a cam surface end the other of which being provided with a cam follower adapted to ride on said cam surface; said cam surface having shoulders to guide said cam follower to move in only one circumferential direction; and means for detecting the location of at least one other pipe string relative to said direction of fire.

7. Apparatus for use in a well bore comprising. a tubular member including means to frictionally engage the walls of a well bore; a mandrel slidably received by said member and adapted to be supported by a cable; said mandrel having indexing slot means arranged about its periphery for rotatively indexing said mandrel relative to said member in one rotative direction only; a follower on said member adapted to cooperate with said slot means to rotate said mandrel relative to said member; a well tool having a selected direction of operation connected to said mandrel for rotation therewith; and means for determining said selected direction of operation of said well tool in said well bore.

8. Apparatus for use in a well bore comprising: a cylindrical member arranged for coupling and movement with a cable; a tubular member slidably received on said cylindrical member, wall engaging means coupled to said tubular member for effectively retarding longitudinal movement of said tubular member relative to the side wall of a well bore so that said cylindrical member may be moved relative to said tubular member; indexing means coupled between said cylindrical member and said tubular member including slot means and a follower for said slot means arranged to promote rotational movement between said cylindrical member and tubular member when said cylindrical member is moved longitudinally relative to said tubular member; said slot means including first longitudinally extending slots and second slots disposed intermediate said first slots and inclined relative to and connecting adjacent first slots to one another, said first slots respectively having a bottom Wall surface at one end adjoining an intermediate bottom wall surface section which includes an inclined bottom wall surface being contiguous with said bottom wall surface at said one end and, said inclined surface extending outwardly away from said bottom wall surface at said one end, said intermediate bottom wall surface section terminating within a first slot at a shoulder formed between the intermediate bottom wall surface section and the bottom wall surface at the remaining end of a first slot, said second slots having corresponding ends connected to the other ends of said first slots adjacent to said shoulders so that said shoulders are contiguous with the side walls of said second slots, said follower being resiliently biased into said slot means with a portion thereof normally disposed adjacent said bottom wall surfaces and movable in response to contact with an inclined bottom wall surface so that, upon movement of said mandrel in one direction, said follower is irreversibly transferred from one end of a first slot to the other and movement of said mandrel in an opposite direction causes said follower portion to be directed into a second slot by a shoulder.

9. Apparatus for use in a well bore comprising: a cylindrical member arranged for coupling and movement with a cable; a tubular member slidably received on said cylindrical member, wall engaging means coupled to said tubular member for effectively retarding longitudinal movement of said tubular member relative to the side wall of a well bore so that said cylindrical member may be moved relative to said tubular member; indexing means coupled between said cylindrical member and said tubular member including slot means and a follower for said slot means arranged to promote rotational movement between said cylindrical member and tubular member when said cylindrical member is moved longitudinally relative to said tubular member; said slot means including first longitudinally extending slots and second slots disposed intermediate said first slots and inclined relative to and connecting adjacent first slots to one another, said first slots respectively having a bottom Wall surface at one end adjoining an intermediate bottom wall surface section which includes a first inclined bottom wall surface, said first inclined surface being contiguous with said bottom wall surface at said one end and extending outwardly away from said bottom Wall surface at said one end, said intermediate bottom wall surface section terminating within a first slot at a first shoulder formed between the end of the intermediate bottom wall surface section and the bottom wall surface at the remaining end of a first slot, said second slots having corresponding ends connected to the other ends of said first slots adjacent to said first shoulders so that said first shoulders are contiguous with the side Walls of said second slots, said second slots respectively having a second bottom wall section which includes a second inclined surface extending outwardly away from said bottom wall surface, at said other end of said first slot, said second bottom wall section terminating within a first slot at a second shoulder formed between the end of said second bottom wall section and the bottom wall surface at the one end of a first slot, said second shoulder being contiguous with the side wall of a first slot, said follower being resiliently biased into said slot means with a portion thereof normally disposed adjacent said bottom wall surfaces and movable in response to contact with an inclined bottom wall surface so that, upon movement of said cylindrical member in one direction, said follower is irreversibly transferred from one end of a first slot to the other and movement of said cylindrical member in an opposite direction causes said follower portion to be directed into a second slot by a shoulder, and subsequently irreversibly disposed in an adjacent first slot by said second shoulder.

10. Apparatus for use in a well bore comprising: a cylindrical member arranged for coupling and movement with a cable; a tubular member slidably received on said cylindrical member, wall engaging means coupled to said tubular member for effectively retarding longitudinal movement of said tubular member relative to the side wall of a well bore so that said cylindrical member may be moved relative to said tubular memher; said cylindrical member having slot means about its periphery including first longitudinally extending slots and second slots disposed intermediate said first slots and inclined relative to and connecting adjacent first slots to one another, said first slots respectively having a bottom Wall surface at one end adjoining an intermediate bottom wall section which includes an inclined bottom wall surface, said inclined surface extending towards the outer surface of said cylindrical member, said bottom wall section terminating within a first slot at a shoulder formed between the end of said bottom wall section and the bottom wall surface at the remaining end of a first slot, said second slots having corresponding ends connected to the other ends of said first slots adjacent to said shoulders so that said shoulders are contiguous with the side walls of said second slots; and a resiliently biased follower on said tubular member received by said slot means, said follower having a portion thereof normally disposed adjacent said bottom wall surfaces and movable in response to contact with an inclined bottom wall surface so that, upon movement of said cylindrical member in one direction, said follower is irreversibly transferred from one end of a first slot to the other and movement of said cylindrical member in an opposite direction causes said follower portion to be directed into a second slot by a shoulder.

11. Apparatus for use in a well bore comprising: a cylindrical member arranged for coupling and movement with a cable; a tubular member slidably received on said cylindrical member, wall engaging means coupled to said tubular member for effectively retarding longitudinal movement of said tubular member relative to a side wall of a well bore so that said cylindrical member may be moved relative to said tubular member; said cylindrical member having slot means about its periphery including first longitudinally extending slots and second slots disposed intermediate said first slots and inclined relative to and connecting adjacent first slots to one another, said first slots respectively having a bottom wall surface at one end adjoining an intermediate bottom wall section which includes an inclined bottom wall surface, said inclined surface extending towards the outer surface of said cylindrical member, said intermediate bottom wall section terminating within a first slot at a shoulder formed between the end of the bottom wall section and the bottom wall surface at the remaining end of a first slot, said second slots having corresponding ends connected to the other ends of said first slots adjacent to said shoulders so that said shoulders are contiguous with the side Walls of said second slots; said tubular member having an annular groove and an opening connecting said groove to the interior of said tubular member; and an arcuate band spring member having a portion extending through said opening into said slot means to form a follower for said slot means, said portion in said slot means being normally disposed adjacent said bottom wall surfaces and movable in response to contact with an inclined bottom Wall surface so that, upon movement of said cylindrical member in one direction, said follower is irreversibly transferred from one end of a first slot to the other, and movement of said cylindrical member in an opposite direction causes said follower portion to be directed into a second slot by a shoulder.

12. Apparatus for use in a well bore comprising: a cylindrical member arranged for coupling and movement with a cable; a tubular member slidably received on said cylindrical member, wall engaging means coupled to said tubular member for effectively retarding longitudinal movement of said tubular member relative to a side wall of a well bore so that said cylindrical member may be moved relative to said tubular member; said cylindrical member having slot means about its periphery including first longitudinally extending slots and second slots disposed intermediate said first slots and inclined relative to and connecting adjacent first slots to one another, said first slots respectively having a bottom wall surface at one end adjoining an intermediate first bottom wall section which includes a first inclined bottom wall surface, said first inclined surface extending towards the outer surface of saidcylindrical member, said first intermediate bottom wall section terminating within a first slot at a first shoulder formed between the first bottom wall section and the bottom wall surface at the remaining end of a first slot, said second slots having corresponding ends connected to the other ends of said first slots adjacent to said first shoulders so that said first shoulders are contiguous with the side walls of said second slots, said second slots respectively having a second bottom wall section including a second inclined surface extending towards the outer surface of said cylindrical member, said second bottom wall section terminating within a first slot at a second shoulder formed between the end of the second bottom wall section and the bottom wall surface at the one end of a first slot, said second shoulder being contiguous with the side wall of a first slot; and a resiliently biased follower on said tubular member received by said slot means, said follower having a portion thereof normally disposed adjacent said bottom wall surfaces and movable in response to contact with an inclined bottom wall surface so that, upon movement of said cylindrical member in one direction, said follower is irreversibly transferred from one end of a first slot to the other and movement of said cylindrical member in an opposite direction causes said follower portion to be directed into a second slot by a first shoulder and subsequently irreversibly disposed in an adjacent first slot by said second shoulder.

13. Apparatus for use in a string of tubing comprising: a tubular centralizer adapted for passage through a string of tubing and including spring means to frictionally engage the walls of the string of tubing; a cylindrical member slidably received by said tubular centralizer and arranged for connection and movement with a cable; said cylindrical member having slot means about its periphery including a plurality of slots extending longitudinally thereof, portions of the bottom wall surfaces of said longitudinal slots being elevated relative to other bottom wall surfaces of said slots to form shoulders facing towards one extremity of said one cylindrical member, a plurality of slots extending transversely to said longitudinal slots respectively having end portions adjoining said longitudinal slots at locations above and below said shoulders, portions of the bottom wall surfaces of said transverse slots adjoining said longitudinal slots above said shoulders being elevated relative to other bottom wall surfaces of said adjoining longitudinal slots to form shoulders lying in the plane of one of the side walls of said longitudinal slots; and a resiliently biased follower on said centralizer received by said slot means and adapted upon relative movement between said cylindrical mem- References Cited in the file of this patent her and said centralizer to follow said slot means and UNITED STATES PATENTS having a portion extending into said slot means so as to 137 074 Hard Mar 25 1873 move between said elevated portions and said other bot- 2 250463 Boyntgt'l 1941 torn Wall surfaces whereby said follower may be trans- 5 2371498 Bolynton "i Mar 1945 ferred irreversibly from the respective elevated portion 2:389:869 Phipps 1945 of one slot to the respective adjoining portion of another 2,780,372 covitt et a1- Feb 5 57 810i. 2 2,998,068 True Aug. 29, 1961 

1. APPARATUS FOR USE IN A WELL BORE COMPRISING: A TUBULAR MEMBER INCLUDING HAVING MEANS TO FRICTIONALLY ENGAGE THE WALLS OF A WELL BORE; A MANDREL SLIDABLY RECEIVED BY SAID MEMBER AND ADAPTED TO BE SUPPORTED BY A CABLE; SAID MANDREL HAVING INDEXING SLOT MEANS ARRANGED ABOUT ITS PERIPHERY FOR INDEXING ROTATIVELY SAID MANDREL RELATIVE TO SAID MEMBER IN ONE ROTATIVE DIRECTION ONLY; A FOLLOWER ON SAID MEMBER ADAPTED TO COOPERATE WITH SAID SLOT MEANS TO ROTATE SAID MANDREL RELATIVE TO SAID MEMBER; AND A WELL TOOL HAVING A SELECTED DIRECTION OF OPERATION CONNECTED TO SAID MANDREL FOR ROTATION THEREWITH. 